From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lf1-f68.google.com (mail-lf1-f68.google.com [209.85.167.68]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by dev.tarantool.org (Postfix) with ESMTPS id AE8CD445320 for ; Wed, 29 Jul 2020 23:06:59 +0300 (MSK) Received: by mail-lf1-f68.google.com with SMTP id i19so13716819lfj.8 for ; Wed, 29 Jul 2020 13:06:59 -0700 (PDT) Date: Wed, 29 Jul 2020 23:06:56 +0300 From: Cyrill Gorcunov Message-ID: <20200729200656.GC3264@grain> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Subject: Re: [Tarantool-patches] [PATCH 1/1] txn_limbo: don't duplicate confirmations in WAL List-Id: Tarantool development patches List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Vladislav Shpilevoy Cc: tarantool-patches@dev.tarantool.org On Wed, Jul 29, 2020 at 01:17:27AM +0200, Vladislav Shpilevoy wrote: > When an ACK was received for an already confirmed transaction > whose CONFIRM WAL write is in progress, it produced a second > CONFIRM in WAL with the same LSN. > > That was unnecessary work taking time and disk space for WAL > records. Although it didn't lead to any bugs. Just was very > inefficient. > > This patch makes confirmation LSN monotonically grow. In case more > ACKs are received for an already confirmed LSN, its confirmation > is not written second time. > > Closes #5144 Ack